1. Technical Field of the Invention
This invention relates generally to rope management devices, and more particularly, to an apparatus for ascending and descending a rope without the assistance of a belayer.
2. Description of the Related Art
Cam cleat devices which permit a rope to move freely in one direction, while automatically engaging and stopping a rope from passing in the opposite direction, are well known.
Examples of such devices are described in U.S. Pat. No. 4,716,630 to Helmut Skyba and U.S. Pat. No. 4,217,847 to Robert McCloud. These devices employ camming apparatus to ascend a rope. However, once a fall has occurred, the rope is jammed so tightly by the cams that all weight must be removed from the device in order to release the rope. For obvious reasons, such devices are not suitable for use as a descender, therefore other systems are required, adding weight and inconvenience to the user's load.
An example of a device specifically designed for descending a rope is described in U.S. Pat. No. 5,076,400 to Paul and Pierre Petzl. Not only is this device not capable of acting as an ascender, the device contains several pulleys and a pre-tensioned spring that requires a threshold adjustment based on the weight of the user to optimize performance of the device. This adds a certain amount of inconvenience to the user, especially if several people are sharing the same climbing equipment.
In U.S. Pat. No. 5,544,723 to Donald Gettemy, a self-belay device suitable for both ascending and descending a rope is described. This device has many components, and in order to use it an end of the rope must be threaded through four different holes. Thus, the device cannot be easily detached and removed unless one is near the end of the rope. Additionally, the device is fairly inconvenient since the rope must be placed in a different configuration depending on whether one is ascending or descending the rope. In some situations this may not be such a detractor, but in typical situations constant up and down adjustments are necessary. Furthermore, when the device is configured as a descender, the rope essentially slides freely through the apparatus. In other words, the user cannot employ the device to provide friction to slow down or speed up the descent, this must be provided by some other means or device.
Embodiments of the invention address these and other disadvantages of the conventional art.